Japanese Patent Application Publication No. 2006-37870 (hereinbelow referred to as Patent Literature 1) describes a vortex pump provided with a motor portion and a pump portion. The motor portion and the pump portion are provided in a housing. The housing is provided with a separation wall that separates the motor portion and the pump portion. Further, the housing has a bearing fixed thereon for supporting an output shaft of a motor. The output shaft of the motor extends from the motor portion to the pump portion in a state of being supported by the bearing. The pump portion is provided with a fluid suction port, a fluid discharge port, and an impeller. A vane-groove region configured of a plurality of vane grooves is provided on an outer periphery of the impeller. Further, a facing groove is provided on the separation wall at a position facing the vane-groove region. In Patent Literature 1, a communication hole communicating the motor portion and the pump portion is provided at a bottom of the separation wall.